Monday, August 29, 2011

The Sterling 9mm Carbine, made by Wise Lite Arms, and distributed by Century Arms International, is a unique firearm with an interesting history. Based on the Sterling submachine gun, the semiautomatic Sterling Mk IV Sporter Carbine maintains much of the original look of the famous 9mm SMG, except for the 16" barrel that protrudes from the original barrel shroud.

The Sterling Mk IV Sporter Carbine, Stock Folded

Like its submachine gun parent, the Sterling Mk IV Carbine comes finished in a black crinkle coat, which seems exceptionally durable. The Mk IV also includes an original folding stock, which folds underneath the barrel and locks into the barrel shroud when closed. The semi-auto carbine uses curved 34 round Sterling magazines, and is compatible with Sten magazines as well (though Sterling magazines will not work in a Sten). Loading a Sterling magazine is mercifully easy on the thumbs thanks to a set of rollers above the magazine spring, instead of a traditional metal or plastic follower. Essentially this ensures that the 34th round loads as easily as the first, which is a welcome feature, and one I wish was offered on other magazines.

The Mk IV Carbine is relatively simple from an operational standpoint. The bolt handle is on the right side, the magazine is inserted in the left. The safety lever must be in the fire position to completely retract the bolt and allow the firing mechanism to be cocked. The safety lever is large, and located on the upper portion of the pistol grip, on the left side. Pushing the lever forward switches it to fire. Its position is easily manipulated (if you're a righty) without moving your hand from a firing position. The bolt, an original part from the Sterling SMG, is interesting in design. It features spiral cut grooves which were designed to help clear debris from the bolt face, which improves reliability. Because the Sterling was originally designed to fire from an open bolt, and because the bolt on the Mk IV Carbine is an original Sterling part, it had to be machined by Wise Lite, and a conventional firing pin added, in order to fire from a closed bolt and be classified by the ATF as a semi-auto rifle. So, while the semi-auto carbine shares many of the same parts with the original Sterling SMG, not all parts from a Sterling parts kit will be compatible with the Mk IV Sporter.

Takedown is easy. A lever on the rear of the receiver, that holds a retaining cap (which also acts as the locking mechanism for the extended buttstock), is pushed in. The retaining cap is pressed down, and rotated, like a childproof medicine bottle. The cap is removed, revealing a set of springs which are removed larger, to smaller, ending in the bolt assembly, sear, and firing pin. Disassembled, the Sterling looks like a tube with some springs in it.

The trigger, also an original Sterling part, has a fairly light pull, and what I can only describe as a natural reset. Of the many 9mm carbines I've fired, the Sterling Mk IV Carbine's trigger is one of the easiest. Combined with light recoil of the round, controlled, rapid fire is as easy as pulling the trigger (really fast). And, it's a lot of fun to boot.

The 16" barrel of the Sterling Mk IV Sporter Carbine lends the gun a surprising degree of accuracy. In keeping with the theme of simplicity, the sights are simple to adjust. A small set screw on the base of the front sight is loosened, and the front sight post is rotated to adjust for elevation, while a brass punch and hammer are used to drift the sight base for windage. The rear sight, though not adjustable in the conventional sense, does flip up and down, and are marked for 100 and 200 meters. I had the gun sighted in at 50 meters in no more than 20 minutes, using very a scientific, custom made target to make my adjustments (a crude 4x5 inch rectangle drawn on a piece of 8x11 paper with a sharpie). After the gun was sighted in, I had little trouble keeping my shots inside the rectangle. The last four of the five shots I fired while sighting in, remained in the rectangle, with one flier just barely outside, using the least expensive 9mm plinking ammo I could find (Russian made Tula 115 grain steel cased FMJ). Using the same ammo, I had little trouble keeping a Do-All Outdoors Top Hat Reactive Target
constantly on the move (which is itself only a few inches wide and tall).

Custom 4x5 Match Target at 50 meters

The Sterling Mk IV Sporter Carbine carries a one year warranty from Wise Lite Arms. Of the three Mk IVs I test fired (and the countless Sterlings that have come through the Ozark Bear Arms store), we've only encountered one that had any malfunctions. On this gun, the problem (which had something to do with how the bolt was machined) was severe enough to require the gun to be sent back to Wise Lite Arms for warranty repair, a process that took about three weeks. Since it came back from Wise Lite, it has had zero malfunctions (in fact, it's one of the guns used in the test fire video above, and is the same that put holes in the test target). Wise Lite Arms is no longer producing a Sterling variant, and as a result, Century will very soon no longer be distributing any. I don't know how this will affect future warranty coverage, but as of this writing, Wise Lite is dutifully honoring warranties on any new firearms.

The Sterling Mk IV is a unique gun from an appearance and design standpoint. It's incredibly user friendly, easy to maintain, has light recoil, a nice trigger, and should appeal to aficionados and casual shooters alike (it's always been a hit at the range with everyone whose fired ours). With Wise Lite Arms now out of the Sterling business, and supplies likely drying up soon, it will inevitably become a difficult gun to find for a reasonable price in the future. Issues we had with one Sterling aside, I have no reluctance in recommending one to someone who is interested in the platform.